From what I know Silent Gliss uses Rako Racub modules for their blinds and Rako Control Plates. If this is still valid then you only need the Rako RAVIR interface and you can control the blinds using IR and without the extender. If you buy the extender then you can still the RAVIR or the RAV232 (RS232 interface). If you decide to use RS232 then you will need the Rako RAV232+ not the Rako RAV232. This is because the Pronto does not support the baud rate of the RAV232. Call Rako directly and they will help you more on this.